isInitialized

Reports the initialized state of the key. Keys must be initialized before
being used.

A Key object sets its initialized state to true only when all the associated
Key object parameters have been set at least once since the time the initialized state was set to false.

A newly created Key object sets its initialized state to false. Invocation of the
clearKey() method sets the initialized state to false. A key with transient key data
sets its initialized state to false on the associated clear events.